1. Field of the Invention
The present invention relates to lighting fixtures and, more particularly, to fluorescent lighting fixtures adapted for permanent mounting in or adjacent to a wall or ceiling.
2. Brief Description of the Prior Art
Illumination devices are commonly found in residential, commercial, or municipal applications. These devices typically take on many forms, depending on the type or intensity of luminance desired.
For example, U.S. Pat. No. 3,702,928 issued to Alger discloses a remote controlled adjustable dental operating light. U.S. Pat. No. 5,672,002 to Todd, Jr. discloses a light assembly that can be secured to a ceiling fan. Other examples include U.S. Pat. No. 3,974,371 to Miles, Jr. which discloses an adjustable light fixture recessible in a ceiling for directing light toward an object at various angles; U.S. Pat. No. 4,881,157 to Pahl which discloses a lamp fixture housing which is recessed in a ceiling; U.S. Pat. No. 5,609,413 to Lecluze which discloses an adjustable light fixture recessed in a ceiling or wall for directing light at various angles; U.S. Pat. No. 5,412,551 to Newell which discloses a luminaire having the shape of a flatened, elongated V and a lamp positioned directly above the point of the V; and U.S. Pat. No. 5,613,766 to Raouf which discloses an adjustable wall mounted luminary made up of a ballast housing and a reflector housing containing a light source.
In general, the prior art can be subdivided into two types of illumination devices- point source lighting fixtures and wide area lighting fixtures. Point source lighting fixtures are defined herein as those illumination devices which provide concentrated localized lighting over a small area, usually via an incandescent bulb. Desk lamps and dentist lamps are examples of point source lighting fixtures. Point source lighting fixtures are generally semi-mobile since they can be connected to a conventional power outlet, either directly or with the assistance of an extension cord. However, point source lighting fixtures are generally not adequate for illumination of large spaces.
To provide illumination for large spaces, wide area lighting fixtures are usually used. Wide area lighting fixtures are defined herein as those illumination devices which provide lighting over a large area, such as conventional overhead incandescent and fluorescent lighting. These types of illumination devices are usually hard wired to a power source and are generally mounted in or adjacent to a wall or ceiling.
Some wide area lighting fixtures have light holders which are multi-directional or otherwise moveable with respect to a frame. Examples include track lighting and the fixtures disclosed in U.S. Pat. Nos. 3,974,371 to Miles, Jr. and 4,881,157 to Pahl. However, there are still numerous disadvantages to these types of multi-directional wide area lighting fixtures. The most significant disadvantage is that these fixtures are designed to accept a single incandescent light source. Incandescent light sources, such as a standard light bulb, generate a tremendous amount of heat during operation. Therefore, the area of the incandescent light source must increase with increased luminosity in order to make the overall surface of the incandescent light source cooler. Due to the limited space in many ceilings, as well as building and fire code regulations, small, bright, hot incandescent bulbs are disfavored, as are cooler but larger incandescent bulbs.
Because of the problems associated with incandescent light sources, as well as energy and safety concerns, fluorescent lighting fixtures having fluorescent light sources are a preferable alternative to incandescent light sources. In general, fluorescent lighting fixtures are less expensive to operate than incandescent lighting fixtures and provide adequate downlighting over a large area. However, known fluorescent lighting fixtures designed to provide conventional downlighting or enhanced directional lighting are not configured to fold, pivot, or otherwise move conveniently out of the way when the need for enhanced lighting is eviscerated. This drawback reduces headspace and is not aesthetically pleasing.
It is therefore an object of the present invention to provide a low-profile, adjustable fluorescent lighting fixture having at least one light holder which is able to extend, pivot, spin, and slide with respect to a housing, mounting surface, such as a ceiling or wall, or another light holder.
By way of example only and without limitation to the following combinations, the light holders of the present invention are adjustable to provide: (a) enhanced fluorescent lighting, (b) fluorescent broadcast lighting, (c) normal fluorescent downlighting, and (d) enhanced fluorescent broadcast lighting. Fluorescent downlighting is defined herein as normal wide area lighting over a general area. Enhanced fluorescent lighting is defined herein as light which is adjustably directed toward a particular location, person, place, or thing, such as during live performances, teleconferencing, filming, videotaping, or accent lighting. Fluorescent broadcast lighting is defined herein as lighting which is particularly designed for use with video, film, or teleconferencing applications and generally includes fluorescent bulbs designed for such applications. Finally, enhanced fluorescent broadcast lighting is herein defined as enhanced fluorescent lighting having fluorescent light sources, such as broadcast quality fluorescent bulbs, designed for video, film, or teleconferencing applications.
Although fluorescent downlighting can also function as fluorescent broadcast lighting if a broadcast quality fluorescent bulb is used, enhanced fluorescent broadcast lighting (which is position adjustable) is preferred in most video, film, or teleconferencing applications. Using a proper fluorescent light source and the proper placement of the light holders is important to create dimensionality and interest. If fluorescent broadcast lighting is used, without enhanced fluorescent broadcast lighting, images may appear flat and shadowy and objects in the foreground recede into the background. The angle at which light strikes a location, person, place, or thing is of great importance with reference to the person or the camera receiving the image.
One embodiment of an adjustable lighting fixture according to the present invention includes a housing forming an interior cavity. A light holder is positioned in the interior cavity of the housing. The light holder is configured to be moved with respect to the housing, and a fluorescent light source is connected to the light holder. The light source is connected to a ballast, which may be configured to receive a digital or analog signal from a controller to dim and brighten the light source. The adjustable fluorescent lighting fixture is movable from a storage downlighting position to an enhanced lighting position and vice versa. A multi-purpose combination according to the invention can be configured to provide fluorescent downlighting when the light holder is in the storage/downlighting position and enhanced fluorescent lighting when the light holder is moved into the enhanced lighting position. As previously stated, if a broadcast quality fluorescent bulb is used, fluorescent broadcast lighting and enhanced fluorescent broadcast lighting may also be provided.
The housing is preferably mounted in or adjacent to a ceiling and hard wired to a power source. Each light holder may include a reflector positioned between the light holder and a light source, a light source clip configured to receive the light source, a safety latch, and filter material. Each light holder is pivotally movable with respect to the housing or is connected to an extension arm which is connected to both the housing and the light holder. The extension arm can be a telescoping glide bracket, a connection plate having slide members slideably engaging the connection plate, or other suitable device. A pivot joint may be positioned between the extension arm and the light holder to allow the light holder to be rotatable at least 90 degrees about a longitudinal axis of the extension arm and to pivot at least 15 degrees with respect to the extension arm.
In another embodiment, the housing is a hollow box generally having a first wall, a second wall, a third wall opposite the first wall, and a fourth wall opposite the second wall. The light holder has a longitudinal axis, wherein the longitudinal axis of the light holder passes through the intersection of the first and second walls and the third and fourth walls of the housing, thereby orienting the light holder in an angled fashion within the housing.
One possible fluorescent lighting system includes an adjustable fluorescent lighting fixture connected to a fixed power source. The adjustable fluorescent lighting fixture has a light holder and a fluorescent light source connected to the light holder. The light holder may be simply stored in a storage position and moved to provide enhanced fluorescent lighting in an enhanced lighting position, or the light holder may provide fluorescent downlighting in the storage position. Finally, the light holder may provide fluorescent broadcast lighting or enhanced fluorescent broadcast lighting. A ballast which is either not adjustable or adjusted, such as by a controller, is connected to the light holder. The controller is connected to the ballast.
In one application, the ballast receives a 0-10 Volt electronic signal from the controller, such as an analog potentiometer. Alternatively, the ballast may receive a digital signal from the controller. In either case, the controller can be manipulated manually, through a computer, or through a remote control. In digital applications, a DMX-512 box may be positioned between the controller and the ballast, wherein a DMX-512 controller sends a digital DMX-512 signal through the DMX-512 box to the ballast. In yet another configuration, a DMX-512 control chip is integrated with the ballast.
In addition to manipulation of the ballast, motors in the housing may also be controlled as discussed above, except that a continuous analog voltage is used, as opposed to a varying analog voltage. In operation, the controller sends signals to the ballasts and motors, either individually or in series, which permits one or more light sources connected to the light holder to be brightened or dimmed and permits the light holder to be moved in at least one direction with respect to the housing. In digital applications, a DMX-512 box or other suitable device is positioned between the controller and the ballasts or motors positioned in the housing.
A method to produce enhanced fluorescent lighting with an adjustable fluorescent lighting fixture equipped with at least one fluorescent light holder is also disclosed. Some steps include:
a. moving the fluorescent light holder from a storage position to an enhanced lighting position with respect to a housing to provide enhanced fluorescent lighting;
b. moving the fluorescent light holder from the enhanced lighting position to the storage position with respect to a housing to provide storage; or, alternatively,
c. moving the fluorescent light holder from the enhanced lighting position to the storage position to provide fluorescent downlighting. In any step, the fluorescent light holder is pivoted with respect to the adjustable fluorescent lighting fixture housing or moved in a direction away from the adjustable fluorescent lighting fixture housing.
As briefly described above, the present invention represents an improvement in the art of illumination. The adjustable fluorescent lighting fixtures disclosed herein can replace existing fluorescent lighting fixtures in retrofit applications or can be installed in new construction. Another benefit of the present invention is that when light holders contained within the adjustable fluorescent lighting fixtures are oriented for storage or normal downlighting, the adjustable fluorescent lighting fixtures resemble standard commercial fluorescent lighting fixtures. A third benefit is that the adjustable fluorescent lighting fixtures are capable of providing enhanced fluorescent lighting. For example, when the need for enhanced fluorescent lighting or enhanced fluorescent broadcast lighting is required, the fluorescent light holders can be moved from a storage position to an enhanced lighting position, and directed to a particular person, place, or thing. When the need for enhanced fluorescent lighting ceases, the fluorescent light holders can be moved back to the storage position.